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Pursuit of the Living Building Challenge can require creativity, flexible thinking and a willingness to embrace alternatives to ideals. That is certainly the case for PAE Engineers‘ new headquarters building in downtown Portland. When limitations precluded creation of a net-positive-energy structure, the project team formed a unique partnership with a local nonprofit developer in order to meet requirements.

鈥淗onestly, I think it’s one of the better stories of the project,鈥� said Ed Sloop, a project manager and chief estimator for general contractor Walsh Construction Co.

The PAE Living Building is expected to become one of the largest commercial buildings in the world to gain certification from the International Living Future Institute. For that to happen, the building must demonstrate over one year that it is producing more energy than it consumes, producing more clean water than it consumes, recycling all wastewater produced on-site, and more.

The ILFI uses seven 鈥減etals鈥� 鈥� place, water, energy, materials, equity, beauty, and health and happiness 鈥� to measure building performance. Energy petal requirements at first stumped designers from ZGF Architects, MEP engineers from PAE and project managers from Walsh Construction. Two years ago, the problem boiled down to simple math: A five-story, 58,000-square-foot building on only a quarter-block would have nowhere near sufficient roof space for enough solar panels to produce needed electricity.

鈥淎s a team we were all kind of disappointed we couldn’t do it all on site,鈥� said Marc Brune, a PAE principal and a project team member. 鈥淭here’s something that’s just elegant about the concept of really modeling it after a plant or tree that’s in the forest that’s doing all of its own energy production and water harvest.鈥�

The building’s innovative solar array, with panels facing east to west and assembled in an undulating, articulated manner to maximize surface area, is projected to have maximum output of 133 kilowatts 鈥� only around one-third of energy needed.

鈥淚f it were a smaller building for the floor area you might be able to get away with it here,鈥� said Walsh project manager Kent Usher, who recently oversaw subcontractor EC Electric‘s installation of the rooftop array.

The project site, in the Skidmore/Old Town Historic District, limited potential solutions. Unlike the well-known Bullitt Center in Seattle, a certified living building also engineered by PAE that has solar arrays overhanging its roof edges, the PAE Living Building could not follow suit.

鈥淏eing a downtown historic district,鈥� Usher said, 鈥渨e had to keep it hidden and under the parapet height so you can’t see it from anywhere.鈥�

Fortunately for the project team, version 4.0 of the ever-evolving Living Building Challenge allows off-site energy production solutions if they are within the same utility district as the project. And after looking around the district, the team targeted the Renaissance Commons affordable housing development on North Argyle Street in the Kenton neighborhood.

Developed by REACH Community Development Corporation and also built by Walsh Construction, the four-story, two-building complex was solar-ready; it already had the structural and electrical components needed to accept a solar array. And Renaissance Commons had three times as much roof space as the PAE Living Building would have.

鈥淚 happened to be working with Kent (Usher), who was in the same role on this other project,鈥� Sloop said. 鈥淪o, having knowledge of both projects 鈥� and the other project had a very large roof and a big footprint; I knew it had good solar orientation 鈥� so I just threw it out there.鈥�

However, installation of the solar array at Renaissance Commons required financial support from PAE Living Building developer Edlen & Co. The firm, which has backed sustainable elements in many of its projects, agreed to cover the $670,000 cost of placing a 207-kilowatt array at Renaissance Commons.

In addition, the arrangement fulfilled a key requirement of the equity petal, which calls for donation of half a cent or more of every dollar spent on the project to a charity or ILFI’s Living Equity Exchange Program. In this case, REACH CDC qualified because of its affordable housing work.

鈥淔rom my perspective, it’s really like a best-case scenario when you have a problem and you come up with a best-case solution,鈥� Edlen & Co. partner Jill Sherman said.

REACH CDC’s CEO, Dan Valliere, said the nonprofit was simply taking advantage of an opportunity presented to it. REACH CDC agreed to pay for operations and maintenance of the Renaissance Commons array in exchange for being able to use the power generated on-site.

鈥淲e didn’t have to do a lot at the outset,鈥� Valliere said. 鈥淚t was a great opportunity to add a feature to the building with our partners doing most of the heavy lifting and still learn through the process.鈥�

Meanwhile, the PAE Living Building will serve as an example of how project teams can creatively pursue living building certification.

鈥淚 personally think it’s a way of thinking of net-zero-energy production that has the potential to increase the benefit of it beyond the one-building footprint and into the broader community,鈥� Brune said. 鈥淚t can achieve the same goal as if you’re putting it on your roof, but with benefits for more people.鈥�